Heat transfer characteristics in rotating tubes with swirl generator

Durmus A., Ayhan T.

Proceedings of the 2nd Biennial European Joint Conference on Engineering Systems Design and Analysis. Part 1 (of 8), London, Canada, 4 - 07 July 1994, vol.64, pp.703-709 identifier

  • Publication Type: Conference Paper / Full Text
  • Volume: 64
  • City: London
  • Country: Canada
  • Page Numbers: pp.703-709
  • Ondokuz Mayıs University Affiliated: No


The mean heat transfer coefficients, for cold water flowing through an axially rotating pipe with a swirling motion, were estimated at different rotating speed of pipe. The swirling motion of the cold water was produced by four opposite positioned slots located at the entry zone of the rotating pipe, which cold water introduced. Number of slots are varied but their dimensions are kept constant. At the inlet of the pipe, the absolute velocity and the angle of tangency of cold water are introduced by slot number and their dimensions and, also rotating speed of the pipe. The experiments are made for 0, 250, 520 and 850 rpm of the rotating pipe. The augmentation of heat transfer was found to be a function of the slot number, rotating speed of the pipe and Reynolds number, and correlation for this function is presented in accordance with experimental set up models. At the same time range of Reynolds numbers and slot numbers, the augmentation can be as much as three times the value for non-swirling turbulent flow. Also it was shown that cold water side Nusselt number for swirling flow in this rotating pipe can be up to one times higher than that for a flow with swirl in the same pipe having two slots, at fixed Reynolds number.